Flame Spray Technologies SprayTech · applied by a HVOF or Plasma process have ... It can be concluded that most coating ... Hydraulic piston rod coated with a ceramic coating

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The information contained in this document is offered as a guide only. It does not formany part of any sales contract as guaranteed performance of the delivered product.

Doc. no. : 05AP.HV.120Issue : 1Date : 11-09-2003

Flame Spray Technologies

SprayTech

The Power of Partnership

HARD CHROMEREPLACEMENT

For many years, Hard Chrome plating has been a

well excepted coating technology, providing good

wear resistance as well as good corrosion

resistance and fine surface finishes. Because the

plating solutions contain hexavalant chromium

ions, which are carcinogenic, many environmental

and financial sanctions, have been imposed

during the last few years. The cost for hard

chrome plating has been on a consistent upwards

trend, and is projected to continue to escalate.

Alternative coatings have been developed over

time and out-perform the hard chrome plating.

Both carbide, metallic and ceramic coatings

applied by a HVOF or Plasma process have

proven to be successful. The availability of a large

number of different materials has created the

opportunity to tailor the coating for a specific

application; resulting in excellent performances.

Flame Spray Technologies bvImpact 4, 6921 RZ Duiven

P.O. Box 1027, 6920 BA Duiven

The Netherlands

Tel: +31 263190140

Fax: +31 263190141

E-mail: [email protected]

Homepage: www.fst.nl

Flame Spray Technologies Inc.3040 Charlevoix Dr. SE

Suite 203 I

Grand Rapids, MI 49546

USA

Tel: +1 6169882622

Fax: +1 6169882629

E-mail: [email protected]

Homepage:

www.flamespraytechnologies.com

COPIES IN PDF FORMAT ARE AVAILABLE,PLEASE CONTACT FLAME SPRAY

TECHNOLOGIES TO RECEIVE A COPY.

FST Distribution/Agent

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SprayTech


Many Ball Valves are now being coated by means of thermal

spraying

Typical materials include:

♦ FST M-654 Stainless Steel

♦ FST M-771 Self Fluxing Alloy

♦ FST M-341 Alloy C

♦ FST K-624. WC-Co

♦ FST K-647 WC-Co-Cr

♦ FST K-854 CrC-NiCr

♦ FST C-604 Cr2O3

♦ FST C-335 Al2O3-TiO2

(Other materials are available)

WEAR RESISTANCE

Chrome plating is often used to resist abrasive

wear, which typically occurs when a hard surface

or particles rub on a part. Although many factors,

such as the erodent composition, size, shape,

rate, velocity and angle of impingement, as well

as part temperature, influence the wear resistance

properties. It can be concluded that most coating

materials out-perform hard chrome plating. These

materials include: FST M-771, FST K-624, FST K-

647, FST K-854, C-335, C-604.

CORROSION RESISTANCE

Hard Chrome plating is often used to protect parts

against atmospheric and sometimes chemical

corrosion. Generally, it can be stated that the

corrosion resistance is improved when coatings

are dense (HVOF & Plasma) and sealed.

Further, the corrosion resistance strongly depends

on the chemical composition of the selected

coating material. Ni-based alloys, and materials

with a high chromium content typically show good

atmospheric and chemical corrosion resistance.

For severe chemical environments Alloy C and

Alloy 625 can be thermal spayed.

0

50

100

150

200

K-647 WC-Co-Cr Chrome Plating

Coating Loss meassured by ASTM G65 Rubber Wheel Test

Coating Loss m3/Nm x 10-15

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SprayTech


Plasma sprayed ceramics provide good oxidation

protection and are resistant to most acids and

alkalies.

Hydraulic piston rod coated with a ceramic coating

TEMPERATURE CAPABILITY

Hard chrome typically has a max. service

temperature of approx. 480 °C (800 °F). Almost all

thermal spray materials have higher service

temperature capabilities and will vary from 580 °C

to 850 °C (1000 °F to 1500 °F).

Advantages of Thermal Spraying

over hard chrome plating:

♦ Elimination of the toxic issues related to hard

chrome plating. Smaller disposal problem.

♦ Bond strength is usually better.

♦ A wide range of materials available to choose

from. Coatings can be engineered to fit an

application.

♦ Many thermal spray materials have no

thickness limitations and high deposit rates

making thick coatings economically feasible.

♦ Thermal spray equipment is smaller, less

expensive and portable

♦ There is no part size limitation for thermal

spraying. If a part cannot be moved into a

shop, the thermal spray equipment can be

used in the field.

♦ Thermal spraying does not affect the base

metal (such as hydrogen embrittlement) and

normally does not require subsequent heat

treatment(s).

♦ The Thermal spray process is much simpler. It

only requires three steps, while Plating

requires at least 8 steps.

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SprayTech


INDUSTRIES

Thermal spray coatings as alternatives to Hard

Chrome plating can be found in many industries

including:

♦ Pump Manufacturing and Repair

♦ Textile Machinery

♦ Printing Industry and repair

♦ Petrochemical

♦ Automotive

♦ Plating Shops

♦ Off-Shore

♦ Earthmoving Equipment

♦ Hydraulics

♦ And many more

THERMAL SPRAY PROCESSES

Flame Spray Technologies has the capability to

offer a complete product, from coating and

application development, to the supply, delivery

and installation of the thermal spray equipment.

Our product range includes:

♦ MP-100-APS/HVOF Systems

♦ M-APS/II Plasma Systems

♦ HV-Air Fuel System

♦ HV-Wire/Powder System

Accomplished with a wide range of thermal spray

materials Flame Spray Technologies is your

partner in thermal spraying.

COMPARISON OF THERMAL

SPRAYING WITH HARD CHROME

PLATING

Hard Chrome plating is a process that transfers

metal ions from a liquid solution to a metallic

surface under the influence of an electric current.

The most common method is deposition from

aqueous solutions, many which are toxic. During

the plating process, water decomposes and

hydrogen is deposited at the surface being plated.

This might cause hydrogen embrittlement of

various steels unless they are heat treated

immediately after the plating process.

Plating is usually limited to the deposition of

relatively thin, dense layers of pure metals or

simple alloys. A limited range of compositions

may be plated. Electrically conductive substrates

are essential, limiting the number of materials that

can be plated without a pre-treatment.

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SprayTech


Thermal sprayed coatings are used extensively

for a wide range of industrial applications. The

technique generally involves the spraying of

molten powder or wire feedstock, the melting

being achieved by oxy-fuel combustion or an

electrical arc (arc spraying or plasma). The molten

particles are accelerated by the hot gas stream,

followed by impacting onto a properly prepared

substrate. Rapid solidification produces an ultra-

fine grained as-sprayed deposit, having the

properties associated with such microstructures.

The materials which are sprayed include most

metallic and carbide based alloys and ceramics.

In fact, virtually any material can be thermal

sprayed as long as it does not decompose prior to

melting.

A wide range of materials can be thermal sprayed

for a variety of applications, ranging from gas

turbine technology to the electronics industry.

Applications include protection from wear, high

temperatures, chemical attack and environmental

corrosion protection.

The various thermal spray processes are

distinguished on the basis of the feedstock

characteristics (wire/powder) and the heat source

employed for melting.

The following thermal spray processes are in use

today:

♦ Combustion flame spraying (with wire or

powder)

♦ High Velocity Oxy-Fuel Spraying (HVOF) with

extremely high flame and powder particle

velocities, creating very dense coatings.

♦ Electric arc spraying, where two electrically

conductive wires are fed into a common arc

point at which melting occurs. The molten

material is continuously atomized by

compressed air.

♦ Plasma spraying, utilizing the high

temperatures and velocities of ionised gas

(plasma)

There are numerous applications of thermal

spraying which are now evolving. The application

of thermal spray coatings to replace Hard Chrome

plating is one example that proves the versatility,

high quality and reliability of this proven

technology.

Documents

Flame Spray Technologies SprayTech · applied by a HVOF or Plasma process have ... It can be concluded that most coating ... Hydraulic piston rod coated with a ceramic coating